The most grievously injured victim of an anti-Semitic mass stabbing attack in a New York City suburb remains in a coma and is unlikely to awaken, his relatives said on Tuesday night.

Josef Neumann, one of five Jewish people stabbed by an attacker during a Saturday night Hanukkah celebration, was struck three times in the head, leaving a wound that penetrated “directly into the brain,” his family said in a statement.

“Doctors are not optimistic about his chances to regain consciousness,” said the family, which also released a photograph of the 71-year-old Mr. Neumann on a hospital respirator with three stitched wounds on his head.